From ff741906ad3cf4b8ca1a958acb013a97a6381ca2 Mon Sep 17 00:00:00 2001 From: Ashok Raj Date: Fri, 11 Nov 2005 14:32:40 -0800 Subject: [IA64] support for cpu0 removal here is the BSP removal support for IA64. Its pretty much the same thing that was released a while back, but has your feedback incorporated. - Removed CONFIG_BSP_REMOVE_WORKAROUND and associated cmdline param - Fixed compile issue with sn2/zx1 due to a undefined fix_b0_for_bsp - some formatting nits (whitespace etc) This has been tested on tiger and long back by alex on hp systems as well. Signed-off-by: Ashok Raj Signed-off-by: Tony Luck --- arch/ia64/kernel/smpboot.c | 114 ++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 108 insertions(+), 6 deletions(-) (limited to 'arch/ia64/kernel/smpboot.c') diff --git a/arch/ia64/kernel/smpboot.c b/arch/ia64/kernel/smpboot.c index 8f44e7d2df66..e9d37bf67d69 100644 --- a/arch/ia64/kernel/smpboot.c +++ b/arch/ia64/kernel/smpboot.c @@ -70,6 +70,12 @@ #endif #ifdef CONFIG_HOTPLUG_CPU +#ifdef CONFIG_PERMIT_BSP_REMOVE +#define bsp_remove_ok 1 +#else +#define bsp_remove_ok 0 +#endif + /* * Store all idle threads, this can be reused instead of creating * a new thread. Also avoids complicated thread destroy functionality @@ -104,7 +110,7 @@ struct sal_to_os_boot *sal_state_for_booting_cpu = &sal_boot_rendez_state[0]; /* * ITC synchronization related stuff: */ -#define MASTER 0 +#define MASTER (0) #define SLAVE (SMP_CACHE_BYTES/8) #define NUM_ROUNDS 64 /* magic value */ @@ -151,6 +157,27 @@ char __initdata no_int_routing; unsigned char smp_int_redirect; /* are INT and IPI redirectable by the chipset? */ +#ifdef CONFIG_FORCE_CPEI_RETARGET +#define CPEI_OVERRIDE_DEFAULT (1) +#else +#define CPEI_OVERRIDE_DEFAULT (0) +#endif + +unsigned int force_cpei_retarget = CPEI_OVERRIDE_DEFAULT; + +static int __init +cmdl_force_cpei(char *str) +{ + int value=0; + + get_option (&str, &value); + force_cpei_retarget = value; + + return 1; +} + +__setup("force_cpei=", cmdl_force_cpei); + static int __init nointroute (char *str) { @@ -161,6 +188,27 @@ nointroute (char *str) __setup("nointroute", nointroute); +static void fix_b0_for_bsp(void) +{ +#ifdef CONFIG_HOTPLUG_CPU + int cpuid; + static int fix_bsp_b0 = 1; + + cpuid = smp_processor_id(); + + /* + * Cache the b0 value on the first AP that comes up + */ + if (!(fix_bsp_b0 && cpuid)) + return; + + sal_boot_rendez_state[0].br[0] = sal_boot_rendez_state[cpuid].br[0]; + printk ("Fixed BSP b0 value from CPU %d\n", cpuid); + + fix_bsp_b0 = 0; +#endif +} + void sync_master (void *arg) { @@ -327,8 +375,9 @@ smp_setup_percpu_timer (void) static void __devinit smp_callin (void) { - int cpuid, phys_id; + int cpuid, phys_id, itc_master; extern void ia64_init_itm(void); + extern volatile int time_keeper_id; #ifdef CONFIG_PERFMON extern void pfm_init_percpu(void); @@ -336,6 +385,7 @@ smp_callin (void) cpuid = smp_processor_id(); phys_id = hard_smp_processor_id(); + itc_master = time_keeper_id; if (cpu_online(cpuid)) { printk(KERN_ERR "huh, phys CPU#0x%x, CPU#0x%x already present??\n", @@ -343,6 +393,8 @@ smp_callin (void) BUG(); } + fix_b0_for_bsp(); + lock_ipi_calllock(); cpu_set(cpuid, cpu_online_map); unlock_ipi_calllock(); @@ -365,8 +417,8 @@ smp_callin (void) * calls spin_unlock_bh(), which calls spin_unlock_bh(), which calls * local_bh_enable(), which bugs out if irqs are not enabled... */ - Dprintk("Going to syncup ITC with BP.\n"); - ia64_sync_itc(0); + Dprintk("Going to syncup ITC with ITC Master.\n"); + ia64_sync_itc(itc_master); } /* @@ -638,6 +690,47 @@ remove_siblinginfo(int cpu) } extern void fixup_irqs(void); + +int migrate_platform_irqs(unsigned int cpu) +{ + int new_cpei_cpu; + irq_desc_t *desc = NULL; + cpumask_t mask; + int retval = 0; + + /* + * dont permit CPEI target to removed. + */ + if (cpe_vector > 0 && is_cpu_cpei_target(cpu)) { + printk ("CPU (%d) is CPEI Target\n", cpu); + if (can_cpei_retarget()) { + /* + * Now re-target the CPEI to a different processor + */ + new_cpei_cpu = any_online_cpu(cpu_online_map); + mask = cpumask_of_cpu(new_cpei_cpu); + set_cpei_target_cpu(new_cpei_cpu); + desc = irq_descp(ia64_cpe_irq); + /* + * Switch for now, immediatly, we need to do fake intr + * as other interrupts, but need to study CPEI behaviour with + * polling before making changes. + */ + if (desc) { + desc->handler->disable(ia64_cpe_irq); + desc->handler->set_affinity(ia64_cpe_irq, mask); + desc->handler->enable(ia64_cpe_irq); + printk ("Re-targetting CPEI to cpu %d\n", new_cpei_cpu); + } + } + if (!desc) { + printk ("Unable to retarget CPEI, offline cpu [%d] failed\n", cpu); + retval = -EBUSY; + } + } + return retval; +} + /* must be called with cpucontrol mutex held */ int __cpu_disable(void) { @@ -646,8 +739,17 @@ int __cpu_disable(void) /* * dont permit boot processor for now */ - if (cpu == 0) - return -EBUSY; + if (cpu == 0 && !bsp_remove_ok) { + printk ("Your platform does not support removal of BSP\n"); + return (-EBUSY); + } + + cpu_clear(cpu, cpu_online_map); + + if (migrate_platform_irqs(cpu)) { + cpu_set(cpu, cpu_online_map); + return (-EBUSY); + } remove_siblinginfo(cpu); cpu_clear(cpu, cpu_online_map); -- cgit v1.2.3-55-g7522